EP 0783109 B1 20010530 - Force measuring device with capacitive pick-up
Title (en)
Force measuring device with capacitive pick-up
Title (de)
Kraftmessvorrichtung mit kapazitivem Geber
Title (fr)
Dispositif de mesure d'une force à l'aide d'un capteur capacitif
Publication
Application
Priority
FR 9515476 A 19951226
Abstract (en)
[origin: EP0783109A1] The measurement device has capacitive sensor(1) which has two capacitors(C1, C2). An interface circuit(5,7,9A,12) is connected to the sensor for providing an output voltage(Vm) which represents the force. An integrator(5) responds to the electrical charge as input, and generates between an output(4) and a reference voltage source(dc), the output voltage(Vm) with a value proportional to the total of the electrical charge input. A periodic control signal(Ph1, Ph2) is generated which provides two successive states, a measuring state and a charge transfer state. Switchable connections(7) respond to the first signal state for raising two armatures(2a,2b) to a first voltage level(V0), and to a second symmetric voltage level (-V0) with respect to the reference level(dc). A charge transfer circuit(9A) accumulates a charge(C3) and during one of the signal states(Ph1), transfers to the integrator(5) a charge representing the charge present on the first armature(2). During the other signal state(Ph2) the previously accumulated charge is eliminated. The charge elimination takes place during the first state(Ph1) of the measuring control signal and the charge transfer(9A) device also inverts the sign of the charge quantity when it is transferred to the integrator.
IPC 1-7
IPC 8 full level
G01P 15/125 (2006.01)
CPC (source: EP US)
G01P 15/125 (2013.01 - EP US)
Designated contracting state (EPC)
CH DE ES FR GB IT LI NL
DOCDB simple family (publication)
EP 0783109 A1 19970709; EP 0783109 B1 20010530; DE 69613092 D1 20010705; DE 69613092 T2 20020124; FR 2742868 A1 19970627; FR 2742868 B1 19980213; US 5821421 A 19981013
DOCDB simple family (application)
EP 96402871 A 19961223; DE 69613092 T 19961223; FR 9515476 A 19951226; US 78016896 A 19961226